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LOUIS LEFRANO, OF TEACY-LE-VAL, FRANCE.

PROCESS OF EXTRACTING SUGAR FROM'JUICES, SIRUPE, 80C.

EPECIFICATION forming part of Letters Patent No. 325,349, datedSeptember 1, 1825.

(No specimens.)

To all whom it may concern.-

Be it known that I, Louis Lnnnanc, a citi zen of the Republic of France,residing at Tracy-le-V al, in the said Republic, have invent-ed a newand Improved Process of EX- tracting Sugar from Juices, Sirups, andMolasses, of which the following is a specification.

It is well known that when thereis dissolved in a saccharinesolutionaqnantity of lime sufticient to saturate the sugar which iscontained in the solution a soluble sucrate of lime is formed. If thissolution of sucrate of lime is subjected to the action of heat, there isobtained an almost insoluble solution of another sucrate, correspondingto the formula of tribasic sucrate, (O,. ,H,,,O,,30a0.) The formula ofthis reaction appears to be the following: 3 (O,, ,H,,O,,20a0) 2(O,.,H,,O,,30a O)+ C,,H,,O,,. This sucrate is separable when heated byfiltration from its mother-waters. The sugar can be disengaged from itby causing the lime to pass into an insoluble state or utiliz ing it forthe purification of saccharine juices and sirups. The inconvenience ofthis process will appear from the preceding formula.

The transtormation of sugar into tribasic sucrate is never complete. Itis then necessary either to recommence and repeat many times thepreceding operations upon the liqold as it becomes more and more spent,or else l toresort to the process of substitution. \Vhatever may be thevalue of these two systems, it results clearly from the precedingformula that this process of extraction of sugar does not give goodresults, except when the quan tity of sugar in the liquid is quiteconsiderable-that is to say, from five to twelve per cent. of sugar.

It isalso well known that there has been applied to the extraction ofsugar from juices, sirups, and molasses the following process, whichconsists in dissolving in the saccharine solution a quantity of limesuiiicient to produce a saturation of the sugar which the so lutioncontains corresponding with the formation of the bibasic sucrate,afterward to add to this solution a certain quantity of the salt of limein solution, corresponding with the quantityof lime which is lacking toobtain an insoluble sucrate, and to add to the mixture an alkaline base.By this process there is obtained cold a precipitate of bibasic sucrateof lime by virtue of the reaction 3 (O,,ll,,O,,2GaO)+ GaOl f NaO 3(O,.,H,,O,,3Gat)) NaCl, in the case, for example, of the employment ofchloride of lime and of soda. This process, which the above theoreticformula indicates as perfect in the sense that all the sugar will becompletely transformed into insoluble sucrate, has never received anyserious industrial application, because of the expense of the soda, and,above all, because the presence in too great quantity of-this reagentrenders the filtration impossible. This process only finds itsapplication in cases where the saccharine liquors operated upon containa very small quantity of sugar.

It results, from what precedes, that the first system only gives goodresults when the liquors contain a very considerable quantity of sugar,while the second, on the contrary, is only useful when the liquidcontains little sugar. Observing this, I have sought, by combining thetwo and somewhat modifying them, to profit by the ad vantages which theypresent and to do away with their inconveniences. I have thusinaugurated a new process of treating molasses, which is the subject ofthe present invention.

The process is divided into two operationsthe first comprising theformation of an insoluble sucrate, the second comprising the treatmentof the mothcr-watersof this sncrate to extract the sugar thereii'rom.

First operalioa-jbrmat0u of an insoluble .s-ucralc.lhe molas; or thedraiuings are brought in a stirring a maratus to a sugar strength oflive to ten per cent. by means ofa cold milk ot'lime containing lime tothe extent of lifty to eighty per cent. of the weight of the sugarcontained in the solution. This quantity of lime will be insufficient toproduce a complete reaction; but it presents the advantage of commencingit without sudden elevation of temperature-a condition essential to alarge formation of bibasic sncra-te, which only, as is known, is thatwhich is most completely decomposed by'hcat into'tribasic sucrate andsugar. Vhen the mixture is quite ICC homogeneous and this reaction takesplace, I

make an addition of quicklime reduced to a which it contains, and Iconvey it to a boiler to be submitted to the action of heat. In proportion as the temperature rises up to the temperature of eentigrade theliquid becomes thick by reason of the formation of tribasic sucrate,which takes place cimpletely when it arrives at the point of ebullitionafter the formula 3(O12H11 11 0) :9 (C12 n n 0) C H O This point beingattained, the excess of lime which I had eliminated to facilitate thetransformation of soluble sucrate into insoluble sucrate is added littleby little to the liquid,which is always maintained at the point ofebullition. The return to the work of this excess of lime" presents twoimportant advantages: it prevents the loss of sugar and renders thesucrate in abetter condition for washing, giving it by the presence ofan excess of lime more porosity, and consequently more permeability.

It is known that thetribasic sucrate of lime is a gelatinous body, andconsequently difficult of filtration. The presence of an excess of limecauses the disappearance of this grave defect. Thus in my system thelime is taken away when its presence is hurtful, and, on the contrary,replaced in the liquid when its presence has become necessary.

When the mixture is effected, I separate the insoluble sucrate from itsmother-waters by sending it,at the temperature above indicated, to thewashing filter-press, either by means of pumps or by means of amonte-jus. The sucrate remains in the apparatus in the form of cakes,which I wash with boiling water, the

mother-waters flowing away to be submitted to the second operation. Thesucrate thus formed is collected and placed in a stirringapparatus,where I make of it a milk of a dilution which renders itsuitable either for the liming of juices or sirups.

Second operationthe treatment of the motherwaters.The mother-waterscollected in the preceding operation containing yet about three percent. of sugar, the preceding process cannot further be applied withsuccess without restoring these mother-waters to their primitive sugarstrength by the addition of a new quantity of molasses. Now I havefound, in doing this, inconveniences which have led me to reject it. Iprefer to employ the following process: The mother-waters pass from thefilter-press into any suitable refrigerator, to be brought to a normaltemperature, or are sent, if circumstances permit, directly into a tank,where they are allowed to cool. \Vhen waters have extracted from them byfiltration, for the same reason,their excess of lime. Then they are sentinto a boiler, which may be furnished with a stirring apparatus.

It is to be remarked here that in view of the small proportion of sugarthe addition of quicklime, even in excess, does. not sufficiently raisethe temperature to form n1onobasic sucrate. I shall have then almostexclusively bibasic sucrate; but as by the action of heat this bibasicsucrate is converted into tribasic sucrate and into sugar, which wouldbe lost or would necessitate an ulterior operation, I add, in theboiler, a solution of chloride of lime in sufifieient quantity to forman insoluble sucrate of lime; I mix intimately; I

heat; then I add a quantity of caustic soda in proportion equivalent tothat of the chloride of lime to be decomposed. As soon as this additionis made, cold or hot,the reaction takes place. Under the action of heatthe bibasic sucrate of lime is decomposed, as is known, into tribasicsucrate and into sugar; but on the other hand the lime set at liberty bythe substitution of the sodium of the soda for the lime of the chlorideof lime is found in a nascent state, which facilitates its combinationwith the sugar already set at liberty, and, finally, all the sugar isobtained in a state of tribasic sucrate.

As I have said, the operation may be made cold; but it is preferable touse heat, whic facilitates the preceding combination, and, moreover,facilitates the ulterior filtration.

WVhen a temperature for the separation of the sucrate is attained, Isend the liquid to the filter-press, in which it is formed into cakes,which are washed and collected, to be employed as hereinabove stated indescribing the first operation.

The excess of lime which had been previously eliminated may be added tothat of the first operation, or replaced, if desired, in themother-waters, after precipitation of the sucrate.

The mother-waters may afterward be treated to extract from them thesaline azotized and organic matters,or be directly utilized forfertilizers.

It will easily be understood that in the sec ond operation, which I havejust described, I may substitute for the chloride of lime any salt oflime whatever; also, that I may replace the soda by any alkaline oralkaline earthy base whatever without departing from the principles onwhich my invention is based.

Even though the two operations described IIO may suffiee to completelyexhaust the saccharine liquors, I reserve to myself the right to repeatthem, if necessary.

lVhat I claim as my invention, and desire to secure by Letters Patent,is

1. The improvement in the art of extracting sugar from saccharineliquid,consisting in adding to the liquid more than sufficient milk oflime and quicklime in powder to produce a soluble suerate of lime,filtering the solution to remove the excess of lime, heatingthe filteredsolution to about 100 eentigrade, re turning to the solution the limepreviously removed by filtration, refiltering to separate the tribasicsucrate of lime from the motherwaters, then adding quicklime to theresulting mother-waters, filtering the mixture to es:- tract the excessof lime, adding to the filtered liquid, first, asaltof lime insufficient quantity to form t-ribasic sucrate of lime, and afterward analkaline or alkaline earthy base to transform the remaining sugar intotribasic sucrate of lime, and, finally, filtering the liquor from thesucrate, all substantially as herein described.

2. In the process of converting the sugar of saccharine solutions intosucrate of lime by first adding lime to produce a bibasic sucrate' O.CREMER, Rom. M. Hoornn.

